1. Field of the Invention
The present invention relates to an image capturing apparatus such as a digital camera or digital video camera.
2. Description of the Related Art
Recently, there has been proposed an image capturing apparatus configured to obtain the incident direction information of light in addition to the intensity of light on the light-receiving surface of a solid-state image sensor, on which a light beam is incident, by arranging a microlens array at a rate of one microlens for a plurality of pixels on the front surface of the image sensor. Such an image capturing apparatus is a so-called plenoptic image capturing apparatus, which is disclosed in, for example, Ren. Ng, and seven others, “Light Field Photography with a Hand-Held Plenoptic Camera”, Stanford Tech Report CTSR 2005-02”.
In addition, many products used as viewfinders to determine compositions at the time of image capturing have been conventionally developed, which display object images on display devices such as liquid crystal panels arranged on the rear surfaces of image capturing apparatuses such as digital cameras.
When, however, reading out video data captured by an image sensor and outputting the data to a display device, there is a temporal delay between the object image displayed on the display device and the actual object due to a processing time for display. As the number of pixels of an image sensor increases, the amount of readout processing from the image sensor increases. This makes the delay between an actual object and a displayed video noticeable.
In addition, as a pixel readout method for an image sensor, there is a general method of performing readout operation by a raster scan scheme. This scheme is configured to perform pixel readout operation sequentially in the rightward direction from the upper left of an image, read out pixels corresponding to one line up to the right end of the screen, and then perform pixel readout operation again from the left end of the screen, one line below the previous line, in the rightward direction. The scheme is configured to repeatedly perform the above series of readout processing up to the lower right of the image. However, forming a video to be used for display upon reading out pixels at all the field angles will greatly increase the delay between the actual object and the video to be displayed. For this reason, there has been proposed a technique of forming an image used for display by skipping pixels, within field angles to be used for display, on a row and column basis.
The following problem arises in an image sensor in which a microlens array is arranged. That is, it is not possible to form an expected display image by skipping pixels of an image sensor at predetermined intervals on a row and column basis without considering the arrangement of a microlens array and the relationship between the microlenses and the respective pixels.